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6/17/21 

AIM 

6.  The Terminal Weather Information for 

Pilots System (TWIP). 

(a) 

With the increase in the quantity and 

quality of terminal weather information available 
through TDWR, the next step is to provide this 
information directly to pilots rather than relying on 
voice communications from ATC. The National 
Airspace System has long been in need of a means of 
delivering terminal weather information to the 
cockpit more efficiently in terms of both speed and 
accuracy to enhance pilot awareness of weather 
hazards and reduce air traffic controller workload. 
With the TWIP capability, terminal weather 
information, both alphanumerically and graphically, 
is now available directly to the cockpit at 43 airports 
in the U.S. NAS. (See FIG 7

1

20.) 

FIG 7

1

20 

TWIP Image of Convective Weather 

at MCO International 

(b) 

TWIP products are generated using 

weather data from the TDWR or the Integrated 
Terminal Weather System (ITWS). These products 
can then be accessed by pilots using the Aircraft 
Communications Addressing and Reporting System 
(ACARS) data link services. Airline dispatchers can 
also access this database and send messages to 
specific aircraft whenever wind shear activity begins 
or ends at an airport. 

(c) 

TWIP products include descriptions and 

character graphics of microburst alerts, wind shear 
alerts, significant precipitation, convective activity 
within 30 NM surrounding the terminal area, and 
expected weather that will impact airport operations. 
During inclement weather, i.e., whenever a predeter-
mined level of precipitation or wind shear is detected 
within 15 miles of the terminal area, TWIP products 

are updated once each minute for text messages and 
once every five minutes for character graphic 
messages. During good weather (below the predeter-
mined precipitation or wind shear parameters) each 
message is updated every 10 minutes. These products 
are intended to improve the situational awareness of 
the pilot/flight crew, and to aid in flight planning prior 
to arriving or departing the terminal area. It is 
important to understand that, in the context of TWIP, 
the predetermined levels for inclement versus good 
weather has nothing to do with the criteria for 
VFR/MVFR/IFR/LIFR; it only deals with precipita-
tion, wind shears and microbursts. 

TBL 7

1

10 

TWIP

Equipped Airports 

Airport 

Identifier 

Andrews AFB, MD 

KADW 

Hartsfield

Jackson Atlanta Intl Airport 

KATL 

Nashville Intl Airport 

KBNA 

Logan Intl Airport 

KBOS 

Baltimore/Washington Intl Airport 

KBWI 

Hopkins Intl Airport 

KCLE 

Charlotte/Douglas Intl Airport 

KCLT 

Port Columbus Intl Airport 

KCMH 

Cincinnati/Northern Kentucky Intl Airport  KCVG 

Dallas Love Field Airport 

KDAL 

James M. Cox Intl Airport 

KDAY 

Ronald Reagan Washington National Air-
port 

KDCA 

Denver Intl Airport 

KDEN 

Dallas

Fort Worth Intl Airport 

KDFW 

Detroit Metro Wayne County Airport 

KDTW 

Newark Liberty Intl Airport 

KEWR 

Fort Lauderdale

Hollywood Intl Airport 

KFLL 

William P. Hobby Airport 

KHOU 

Washington Dulles Intl Airport 

KIAD 

George Bush Intercontinental Airport 

KIAH 

Wichita Mid

Continent Airport 

KICT 

Indianapolis Intl Airport 

KIND 

John F. Kennedy Intl Airport 

KJFK 

LaGuardia Airport 

KLGA 

Kansas City Intl Airport 

KMCI 

Meteorology 

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